POS0178 ASSOCIATION BETWEEN KNEE MR IMAGING MARKERS AND KNEE SYMPTOMS OVER 7 YEARS IN YOUNG ADULTS
Authors: B. Antony, A. Venn, L. Blizzard, L. March, F. Cicuttini, F. Eckstein, G. Jones, C. Ding, A. Singh
Journal: Annals of the Rheumatic Diseases (2022)

Background Knee magnetic resonance imaging (MRI)-based morphological markers (quantitative biomarkers) and structural abnormalities (semi-quantitative biomarkers) are known to be associated with the progression of knee osteoarthritis (OA). However, there is conflicting evidence on the association between knee MRI-based morphological markers and knee symptoms. Besides, there is a lack of evidence on the clinical significance of MR imaging markers in the general population-based young adults. Hence, our aim was to investigate the associations between MR imaging biomarkers and knee symptoms in middle-aged adults followed over seven years. Objectives To describe the associations of cartilage volume, cartilage thickness, subchondral bone area, cartilage defects, and bone marrow lesions (BML) with knee symptoms in young adults followed up over 6-9 years. Methods Knee symptoms (pain, stiffness, and dysfunction) were assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scale during Childhood Determinants of Adult Health (CDAH)-knee study at baseline (year: 2008-10, age: 30–40 years) and 6-9 year follow-up (CDAH-3; year: 2014–2019, age: 36–49 years). Knee MRI scans were obtained at baseline and were assessed quantitatively for morphological markers such as cartilage volume, cartilage thickness, subchondral bone area using semi-automated segmentation (Chondrometrics, Germany). Cartilage defects and BMLs were assessed using semi-quantitative scoring systems. Univariable and multivariable (adjusted for age, sex, and body mass index (BMI)) zero-inflated Poisson (ZIP) regression model with random effects were used to describe the cross-sectional and longitudinal associations. Results The prevalence of knee pain at baseline (mean age (SD): 34 (2.7); female 49%) was 34% that increased to 50% over 6-9 year follow-up (mean age (SD): 43 (3.2)). Cross sectionally, there was a weak but statistically significant negative association between medial femorotibial compartment (MFTC) [Ratio of Mean (RoM)= 0.99971084; 95% CI: (0.9995525, 0.99986921; p&lt;0.001], lateral femorotibial compartment (LFTC) [RoM=0.99982602; 95% CI: 0.99969915, 0.9999529; p=0.007], and patellar cartilage volume [RoM=0.99981722; 95% CI: 0.99965326, 0.9999811; p=0.029] with knee symptoms. Similarly, there was a negative association between patellar cartilage volume (RoM=0.99975523; 95% CI: 0.99961427, 0.99989621; p=0.014), MFTC cartilage thickness (RoM= 0.72090775; 95% CI: 0.59481806, 0.87372596; p=0.001) and knee symptoms assessed after seven years. The total bone area was consistently and negatively associated with knee symptoms at baseline [RoM= 0.9210485; 95%CI: 0.8939677, 0.9489496; p&lt;0.001] and over seven years (RoM=0.9588811; 95% CI: 0.9313379, 0.9872388; p=0.005). Presence of any cartilage defect or BML was associated with higher knee symptoms at baseline and after seven years. Conclusion In the middle-aged adult population, BML and cartilage defects were positively associated with knee symptoms, whereas cartilage volume and thickness at MFTC and total bone area were weakly and negatively associated with knee symptoms. These results suggest that the quantitative and semi-quantitative MR imaging biomarkers can be explored as a marker of the clinical progression of OA in a young adult population. Disclosure of Interests Benny Antony: None declared, Alison Venn: None declared, Leigh Blizzard: None declared, Lyn March: None declared, Flavia Cicuttini: None declared, Felix Eckstein Shareholder of: Shareholder of Chondrometrics, image processing company, Graeme Jones: None declared, Changhai Ding: None declared, Ambrish Singh: None declared